RESUMO
Feeding of chemically synthesized [27-13C]codisterol ([27-13C]2), [27-13C]24-epicodisterol ([27-13C]3), [23,24-2H2]codisterol ([23,24-2H2]2), and [26,27-2H6]24-methyldesmosterol ([26,27-2H6]8) to Oryza sativa cell cultures, followed by MS and NMR analysis of the biosynthesized dihydrobrassicasterol (9)/campesterol (10), revealed that both (24R)- and (24S)-epimers of 24-methyl-Delta25-cholesterol (2/3) were converted to 9 and 10 via the common intermediate 24-methyldesmosterol (8).
Assuntos
Colesterol/análogos & derivados , Fitosteróis/biossíntese , Plantas/metabolismo , Células Cultivadas , Colesterol/biossíntese , Colesterol/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Oryza/metabolismo , Fitosteróis/químicaRESUMO
Steroidal allylic alcohols formed Na+ adduct ion peaks [M+Na]+ by the addition of NaCl in FAB mass spectrometry. A comparison of the intensities of the adduct ion peaks of allylic alcohols with those of the corresponding saturated alcohols and olefin suggested that the olefinic double bond and the proximal hydroxyl group had coordinated to Na+. The adduct ion was stable and did not undergo dehydroxylation. We suggest that the Na+ adduction will be useful for the molecular weight determination of allylic alcohols which are susceptible to dehydroxylation under FAB mass spectrometric conditions. Na+ adduct ions of alpha,beta-unsaturated carbonyl compounds were also investigated.
